Pressure gauges are often used for determining internal pressure of tires, inflatable bladders, tanks, canisters, and other pressurized containers. The tips of conventional pressure gauges include a cylindrical cup and a center post. The cylindrical cup is configured to be placed over and pressed against the end of a valve stem tube of a valve to form an airtight seal between the pressure gauge and the valve. The center post is configured to depress a valve stem core of the valve to release pressurized air or gas into the pressure gauge.
If the cylindrical cup and the valve stem tube are not perfectly aligned, some of the released air or gas escapes. This causes a significant pressure drop as the remainder of the released air enters the pressure gauge and thus results in inaccurate pressure readings. Furthermore, the center post may not fully depress the valve stem core if the pressure gauge is not aligned with the valve. A reduced amount of air or gas is released, which further contributes to inaccurate pressure readings. The center post may also impart a side force onto the valve stem core if misaligned, which may damage the valve stem core and may prevent the valve from fully closing.
Another challenge with conventional pressure gauges is that the cylindrical cup is configured to overlap the valve stem tube, which makes it difficult to visually determine whether a proper seal has been formed. Users also cannot tell whether an initial seal has been broken and thus may erroneously assume the initial seal remains for the duration of the pressure test.